Naylor said many of the park staff on hand for the roundup are certified emergency medical technicians and responded immediately.

The crash happened just yards from where they were working aroundthe corrals.

Fifty-four horses had been rounded up before the crash.

Naylor said all the horses were being released back into the park andanother roundup likely would be scheduled next year.

The park uses helicopters to round up wild horses and bison and to spray for weeds.

Naylor said helicopters have been used in roundups for about 20 years because they are the most cost-effective method.

The horses are driven to an area where two long fences make a "V" shape that funnels the animals into the corral.

The helicopter had made a couple of herding runs Thursday morningbefore the crash.

The pilot of the Bell 206 helicopter was certified through the federal Interior Department and had recently helped with a bison roundup in South Dakota's Wind Cave National Park, Naylor said.

McBride had last worked at Theodore Roosevelt National Park in 2004 and 2005, helping round up bison, Naylor said.

The Interior Department was sending an investigator to the scene, Naylor said, though she did not know when that person would arrive.

Frank Kuntz of Linton said he has been watching the park roundups since the 1980s.

In other years, he said, the helicopter stayed farther back from the corral fences and people herded the horses around the corrals.

"I've never seen them come in that far with the chopper before," Kuntz said.

His brother, Leo, said he was on a walkway on top of the corrals when the helicopter crashed. He said the helicopter was between twofences and when it lifted and moved to the side, one of its landing skids caught on the fence and flipped the craft to the ground.

"That's pretty close quarters," he said.

Naylor said the helicopter was following a safety plan but said "everything will be investigated."

She knew of no other helicopter crashes during roundups at the park.

"It's definitely a shock to have something like this happen," she said "We plan for it. We prepare for it. We never expect it to happen."

Theodore Roosevelt is one of only five national parks with wild horses, and the only park west of the Appalachian Mountains where the animals roam.

Most of the nation's wild horses are managed by the federal Bureau of Land Management.

The horses in the North Dakota park are descendants of ranch stock that were running loose in the North Dakota Badlands when the park was fenced in the 1950s, Naylor said.

Some horse breeders believe they are descendants of horses the Plains Indians used, but Naylor said there is no way to genetically prove that theory.

"They're considered a historic exhibit," Naylor said.

"They kept them in the park after the park was fenced so that peoplecould see free-roaming horses."

Oehler, in an interview before the roundup began, said the horses are spread out throughout the 70,000-acre park.

He said the helicopter is used to move the horses into groups and then drive them to the corral area.

"The horses are notorious for being crafty," he said. "Once they figure out they can just turn around and go the other direction, they've got you. You want to keep them moving, a nice, slow steady move. Don't give them too much time to think."

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